Need quick rundown 5.7 hemi apart

Apparently piston and/or rod failure is fairly common. My brother bought a 5.7 Hemi for his Warlock and got it cheap because it had a bad plug and the guy scavenged another for his other 5.7. I'm not sure how they fail, but apparently they do. I googled 5.7 Hemi piston and got a whole lot of info popping up.